Can't install Tcl 8.4.4

Hello,
I'm trying to build a LFS system. I'm working with Mandrake 9.2 and using LFS
5.0 book (french version).
Evrything goes fine up to installing Tcl8.4.4. When I try to build the package
(make) I have this error:
gcc -pipe -c -O -D__NO_STRING_INLINES -D__NO_MATH_INLINES -DTCL_DBGX= -Wall
-Wconversion -Wno-implicit-int -fPIC -I./../generic -I. -fno-inline
-DHAVE_UNISTD_H=1 -DHAVE_LIMITS_H=1 -D_LARGEFILE64_SOURCE=1
-DTCL_WIDE_INT_IS_LONG=1 -DHAVE_GETCWD=1 -DHAVE_OPENDIR=1 -DHAVE_STRSTR=1
-DHAVE_STRTOL=1 -DHAVE_STRTOLL=1 -DHAVE_STRTOULL=1 -DHAVE_TMPNAM=1
-DHAVE_WAITPID=1 -DHAVE_UNISTD_H=1 -DHAVE_SYS_PARAM_H=1 -DHAVE_SYS_TIME_H=1
-DTIME_WITH_SYS_TIME=1 -DHAVE_TM_ZONE=1 -DHAVE_GMTIME_R=1
-DHAVE_LOCALTIME_R=1 -DHAVE_TM_GMTOFF=1 -DHAVE_TIMEZONE_VAR=1
-DHAVE_ST_BLKSIZE=1 -Dstrtod=fixstrtod -DSTDC_HEADERS=1 -DHAVE_SIGNED_CHAR=1
-DHAVE_LANGINFO=1 -DPEEK_XCLOSEIM=1 -DHAVE_SYS_IOCTL_H=1
-DTCL_SHLIB_EXT=\".so\" ./../compat/strstr.c
../compat/strstr.c: In function `strstr':
../compat/strstr.c:67: error: `NULL' undeclared (first use in this function)
../compat/strstr.c:67: error: (Each undeclared identifier is reported only
once
../compat/strstr.c:67: error: for each function it appears in.)
make: *** [strstr.o] Error 1
I tried to do the same with the version 8.4.5 and I have the same error.
When I do TZ=UTC make test, the same error again! (with the function strstr)
Do I go ahead with make install despite this error?
Thanks for your help!